Shoe sewing machines



Oct. 3, 1961 F. ASHWORTH ETAL SHOE SEWING MACHINES 3 Sheets-Sheet 1Original Filed Oct. 28, 1955 Inventor; Fed Ash worth Joseph RfoannilliBy their Attorney EMKH Oct. 3, 1961 F. ASHWORTH ETAL 3,002,475

SHOE SEWING MACHINES 3 Sheets-Sheet 2 Original Filed Oct. 28, 1955 Oct.3, 1961 F. ASHWORTH ETAL 3,002,475

SHOE SEWING MACHINES 5 Sheets-Sheet 3 Original Filed Oct. 28, 1955 SHOESEWING MACHINES Fred Ashworth, Wenharn, and Joseph R. Ioanniiii,Beverly, Mass, assignors to United Shoe Machinery (301'- poration,Remington, N.J., a corporation of New Jersey Original application Get.28, 1955, Ser. No. 543,428, new Patent No. 2,928,361, dated Mar. 15,1960.. Divided and this application July 23. 1958. 'Ser.'No. 750,410

11 Claims. (Cl. 112-60) This invention relates generally to improvementsin shoe sewing machines, and more particularly to presser foot actuatingmechanisms employed in such machines. The present application is adivision of application for United States Letters Patent Serial No.543,428, filed October 28, 1955, now Patent No. 2,928,361, granted March15, 1960, in the names of the-present inventors and although the novelconcepts of the present invention are described and illustrated hereinin connection with a shoe sewing machine of the McKay type, it will beappreciated that they are equally applicable to a variety of sewingmachines intended to operate upon materials of widely varyingcharacteristics and thicknesses. However, the many advantages of thedescribed and claimed improvements are more readily apparent whenrelated to a machine such as the present one which is intended tooperate upon work pieces ranging in thickness between A and 1% and'rhaving compressibility characteristics ranging between relatively softrubbers and woods of substantial hardness. it is accordingly an objectof the present invention to provide a presser foot actuating mechanismwhich may be accurately and readily adjusted 'by an operator for workpieces of varying characteristics and to achieve substantial differencesin the appearance ofthe product.

Another object is to provide mechanism forautomatically raising thepresserfoot out of engagement with the work piece at the end of a-seam,and which may be quickly adjusted for effecting release of the workpiece either earlier-or later in accordance with its thickness.

Still another object is to provide a machine in which necessaryadjustment for operating on work pieces of different thicknesses orcharacter'istim may be accomplished without the need for removingportions of the machine housing or enclosing frame.

Still another object is to provide a heavily constructed sewing machinein which the presser foot is positively locked during appropriateportions of the sewing cycle and is quickly released for "work feed.

In the achievement of the foregoing objects a feature of the inventionrelates to a presser foot actuating mechanism operated by a cam on thesewing shaft of the machine through a slot and sliding block joint. Inprior art machines such as that disclosed in United States LettersPatent No. 2,331,118, granted October 5, 1943, in the name of JosephGouldbourn andThomas A. Kestell, a sliding block joint is incorporated,but so inaccessible is it that'it is necessary to stop the machine,remove a portion of the enclosing frame, and reach in among othermechanisms in order to make the adjustment. Accordingly, the movementimparted tothe presser foot may be regulated only by time-consumingtrial and error adjustments. in the present machine, however, thesliding block is connected by "a'linkage to a shaft which extendsthrough the machine-enclosing frame toan adjusting segment adjustablyfixed upon the outer surface of the frame.

Another feature relates to a novel mechanism for automatically raisingthe presser foot out of engagement with the work piece at the end of thescam. The present construction includes a driving and stopping mechanismhaving an arm actuated during final stopping movement of themachine tocause'the presser foot to release the 3,dh2,475 Patented Get. 3, i961 ofengagement with the work piece at a given time in the sewing cyclewithout regard to the thickness of the Work piece, adjustableconnections are included in the present construction for varying thetime at which the presser foot is raised. The presser foot lifting armof the driving and stopping mechanism is coupled to a rockshaft througha novel movable sleeve arrangement. Movement of the rockshaft causes thepresser foot to be lifted out of engagement with the work. By means of alever on the outside of the enclosing frame, the position of one of thesleeves on the rockshaft is adjustable according to the thickness of thework being operated upon to cause the presser foot to belifted eitherearlier or later in the sewlug cycle.

For providing positive locking of the presser foot another feature ofthe invention relates to a novel presser foot lock comprising a ratchetmember on the bar which supports the presser foot. The ratchet isengageable by one or more of a set of pawls which are actuated by a camfor causing the presser foot to be released to feed the work piece.

The foregoing objects, features, and numerous advantages of the novelconstruction will be more fully appreciated from the following detaileddescription ofan illustrative embodiment of the invention takeninconnection with the accompanying drawings, in which PEG. 1 is aperspective view looking from theright side and front of a McKay typelockstitch shoe sewing machine in which the features of the presentinvention are embodied;

FIG. 2 is a View in right side elevation, partly broken away, and on anenlarged scale of the head of the machine shown in FIG. 1'; g

FIG. 3 is a detail perspective view looking from the right front of themachine and from above, showing the presser foot and its actuatingmechanism;

a calipering member connected therewith;

FIG. 5 is a sectional view on an enlarged scale taken along the line V-Vof FIG. 3; and

FIG. 6 is a similar sectional view taken along the line VI--VI of FIG.3.

The illustrated machine is generally similar to the lockstitch McKaytype, rotary horn shoe sewing machine disclosed in United States LettersFatent No. 2,670,701, granted March 2, 1954, in our names. Referring toFIGS. 1 and 2 of the drawings, the machine is provided with stitchforming devices including a straight reciprocating hook needle 2, astraight awl 4, a multiple beak deeptoothed shuttle or loop taker 6, anda rotating needle threading looper in the form of a whirl (not shown) atthe upper end of a work support comprising a rotary shoe entering horn8, the horn having a needle receiving opening at its upper end inalinernent with the needle. To clamp a shoe on the horn a presser footit) having a forked end is secured to the lower end of a verticallyreciprocating presser foot bar 12 at the side of the work with theneedle, the needle passing through the fork in the foot. To actuate thestitch forming devices the machine has mechanisms driven by a sewingshaft 14.

In order to enable work of greater thickness than heretofore to beoperatedupon, the needle and awl of the present machine are actuatedwith a greater reciprocating movement than in prior machines and thelengths of these work penetrating instruments have been correspondinglyincreased to accommodate essential clearances when Work up to athickness of 1% inches is being sewn. For actuating the needle and awl,they are secured to the lower ends of separate reciprocating bars 16 and418 (FIG. 1) respectively, which are retained for sliding movementwithin a box-like carrier 20, the needle moving laterally in a directionof work feed while in engagement with the work a distance equal to thelength of a stitch to impart feeding movement to the work. For acomplete disclosure of the mechanism for actuating the needle and awl,reference may be had to the above-identified parent application and toUnited States Letters Patent No. 2,737,134, granted March 6, 1956, andNo. 2,767,004, granted October 16, 1956, both issued upon applicationsfiled in our names.

The multiple beak loop taker 6 of the present machine is constructedwith five double beaks, the present fivebeak shuttle differing from thatin the machine of Patent No. 2,670,701 by the provision of an additionalbeak. The arrangement of the beaks is generally similar to that in thepatented machine and each beak is brought successively to a position forreception of a loop of thread drawn through the work by the needle whilea loop previously formed and carried about a locking thread case withinthe shuttle is being contracted. As each loop is carried about thelocking thread case the shuttle causes the stitch formed by thepreceding loop to be drawn into the work and the stitch thus formed tobe set securely at a predetermined position within the work. Theshuttle, its drive and associated mechanisms are more fully described inthe parent application.

In order to provide thread for each succeeding loop of thread drawnthrough the work by the needle, a combined thread controller andpull-01f member 22 is provided, as seen in FIG. 1. The controller isactuated while each loop of thread is being enlarged by the shuttle todraw back a short length of thread from the work so that it will beavailable as the threaded needle is retracting from the work.

The presser foot is actuated to clamp, to release and to be raised fromengagement with the work a uniform distance during each sewing cycle ofthe machine, regardless of the thickness of the work operated upon, bymechanism driven from the main sewing shaft. Also associated with thepresser foot is a work calipering feeler 38 (FIG. 3) mounted with thepresser foot and arranged for automatically adjusting the amount ofthread measured by that mechanism as the work varies in thickness. Thefeeler 38 and the thread measuring mechanism connected with it are notrelated to this invention and so will not be described further but afuller understanding may be gained by reference to the parentapplication.

'Referring more particularly to FIGS. 3 to 6, inclusive, the mechanismcontained within the head frame indicated at 40 for actuating thepresser foot to clamp and release the work and to be lifted fromengagement with the work is generally similar to that disclosed ininventors prior Patent No. 2,670,701. Provision is also made to lift thepresser foot manually from the work. To actuate the presser foot themain sewing shaft 14 carries a single cam disk 42, shown in FIG. 3, intwo parts broken along a plane intersecting the sewing shaft at rightangles and the parts illustrated in separated relation for the sake ofconvenience. At either side of the cam disk is cut a groove engaged byone of a pair of cam rolls 44, 46. The cam rolls 44 and 46 are rotatablymounted on two operating levers 48 and 50, respectively, fulcrumed on acommon shaft 52 having its ends rotatably mounted in bearings projectingfrom the head frame 40. The two levers 48 and 50 are operativelyconnected to reciprocate the presser foot bar 12 and to lock and unlocka presser foot lock, respectively. The lifting connections between thepresser foot bar and the lever 48 comprise a horizontal rockshaft 54mounted for rotation in bearings on the head frame and provided with apresser foot lifting arm 56 at its forward end connected through a link58 to a block 60 secured to the presser foot bar 12. The hub of the arm56 surrounds the rockshaft 54 and is formed with a split clamp by whichit is. fixed to a sleeve 62 rotatably mounted on the rockshaft. Thesleeve 62 also has projecting from it an integral arm 64 connected tothe lower end of a link 66, the upper end of which is pivotallyconnected at a point 68 midway between the ends of a floating lever 70.The floating lever also has the presser foot lock connected to one pointalong its length near one end and the operating lever 43 connected toanother point near the other end.

To connect the presser foot lock with the floating lever 70, thefloating lever is forked and surrounds a central wedge 72 and has atopposite sides of it a pair of wedges 74 through all of which passes aconnecting pin 76. The Wedges 72 and 74 comprise the presser foot lockwhich is constructed in a manner similar to that of the lock disclosedin United States Letters Patent No. 2,056,670, granted October 6, 1936,upon an application of Gouldbourn et a1. Between the wedge 72 and one ofthe wedges 74 is interposed a zig-zag series of rolls 78 and between thewedge 72 and the other wedge 74 is interposed a spacing block 80. Tolock and unlock the presser foot bar the uppermost roll of the series isengaged by an arm of an offset lever 82 rotatable in the head frame. Theoffset lever is pressed yieldingly against the uppermost roll to lockthe presser foot. Another arm of the lever is disposed beneath one armof the lock actuating lever 50. During sewing operations the lever 50unlocks the presser foot to enable the presser foot to adjust itsposition with varying thicknesses of work as the sewing progresses.

The point of connection'of the floating lever 70 with the presser footlifting lever 48 is defined by a pin 83 passing through the floatinglever and the bifurcated upper end of a link84. The link 84 hasprojecting from it a pivot 86 passing loosely through a block 88slidably mounted within an arcuate slot in one of the arms of thepresser foot lifting lever 48. The lower end of the link 84 is pivotallyconnected by a screw 90 with a link 92, in turn pivotally connected by ascrew 94 with a downwardly extending arm 96 on a shaft 98. As the mainsewing shaft 14 is rotated the lever 48 is oscillated to raise and lowerthe link 84, the floating lever 70 connected to it acting about theconnecting pin 76 as a fulcrum to rock the sleeve 62 and lift and lowerthe presser foot out of and into engagement with the work through thearm 56 and the link 58.

To enable the presser foot to be unlocked and lifted manually fromengagement with the work, the shaft 54 inside the sleeve 62 has mountedfor free rotation on it near its forward end a handle lever 100. At itsrearward end the shaft 54 has keyed to it with freedom for slidingmovement a spool 102 provided with projecting hubs. One hub is cut witha series of three steps engageable slidingly with a right angle corneron an unlocking sleeve 104 mounted for free rotation on the shaft 54.The unlocking sleeve has projecting from it a segmental earn 106 locatedfor engagement with one arm of a lever 108 rotatable on a fixed stud110. Another arm of the lever 108 has pivotally connected to it thelower end of a vertical link 112, the upper end of which is connected toone arm of the offset lever 82. To press the roll engaging arm of theoffset lever 82 yieldingly against the uppermost roll 73, :1 lug on thelever 198 supports one end of a spring 114 compressed between the lugand a fixed portion of the head frame. The spring 114, therefore, servesto hold the presser foot lock in locked condition except when unlockedby the lever 50. When the handle lever is rotated in a clockwisedirection, as viewed in FIG. 3, an offset arm thereon moves intoengagement with a projection on a collar 116 pinned to the forward endof the shaft 54. Continued rotation of the handle lever rocks the spool102 and causes the unlocking sleeve 104 to be rotated, the lever 108moving in the proper direction to disengage the offset lever 82 from theuppermost roll 78, thus unlocking the presser foot lock. Furtherrotation in a clockwise direction of the a oe-2,415

T handle lever 1% brings a segmental projection 118 on the unlockingsleeve 104 into engagement with a similar projection 120 on the sleeve62 to which is clamped the presser foot lifting arm 56. Additionalrotation of the handle lever thereafter lifts the presser foot from thework to free the work for removal or adjustment of its position withrelation to the stitch forming devices. The projection 118 extends aboutthe shaft 54 through an angular extent of 90, whereas the projection 12%extends through an angle of 180, leaving an angle of 90 for freerelative movement between the unlocking sleeve 194- and the sleeve 62.

The free relative movement between the sleeves 1G4 and 62 is provided toenable the presser foot to be unlocked and then to be raised fromengagement with the Work in successive steps. All of the free relativemovement is necessary in order to ensure unlocking when the presser footengages the thinnest work for which the machine is intended to operate.As the work increases in thickness it is desirable to limit the amountof relative movement between the sleeves 104 and 62.

To enable the greatest relative movement between the sleeves 104 and 62when work of minimum thickness is being operated upon, the spool 162 ismoved along the shaft '54 to bring its lowest step into engagement withthe right angle corner on the rearward end of the sleeve lttd. As shownin FIG. 3, an intermediate step engages the corner of the sleeve iii-tso as to adjust the relative movement between the sleeves 194 and 62 formedium thickness work. When the highest step on the spoolis brought intoengagement with the corner of the sleeve 11M, the presser foot will beunlocked and raised in proper sequence from work of maximumthickness.Thus, the presser foot lock is unlocked earlier with thin work and laterwith thick work as the rockshaft 54 is rocked.

To shift the position of the spool 102 along the shaft 54'so as to bringdifferent steps on the spool into engagement with the corner of thesleeve 164, the space between the flanges of the spool W2 is entered bythe ends of a fork 122 secured to a horizontal shaft 12% rotatablymounted in the right side wall of the head frame 40. Outside the headframe the shaft 124 has integrally connected to it an adjusting arm 126carrying a spring pressed plunger 128 arranged to enter one of a seriesof openings 13% formed in a boss on the head frame. Retraction of theplunger 128 from the boss enables the spool m2 to be shifted to one ofthree positions depending upon the thickness of the work intended to beoperated upon.

For the purpose of adjusting the distance by which the presser foot islifted automatically from clamping engagement with the work duringsewing operations, means are provided for varying the effective lengthof the slotted arm on the operating lever 48. To this end the shaft 38extends through the front wall of the head frame 40 and has integrallyconnected with it an arcuately slotted adjusting segment 132 arranged toswing along the surface of apad on the front of the head frame. Anyswinging movement imparted to the segment 132 rocks the shaft 98 and thearm 96 to impart movement to the lower end of the link 84 through thelink 92, causing the block 88 to shift its position in the slot of thepresser foot operating and lifting lever 48. For securing the segment132 in the position to which it is adjusted, the slot :in the segmenthas passing through it a clamp screw r134 threaded into the pad onthehead frame. The seg- 'ment 132 being exposed on the outer surface of thehead frame is readily accessible for actuation to increase or decreasethe lifting movement imparted to the presser foot by the lever 48, theslot in the lever and the block 83 serving as a simple and effectivelength varying means for the presser foot lifting and loweringmechanism.

At certain times in each sewing cycle, particularly at the time in whichthe threaded needle starts to withdraw it'sloop of thread from the work,it is dcsiiable'to avoid d any possibility of-work displacement.Accordingly, in the illustrated machine a second lock is connected tothe presser foot for resisting lifting movement of the presser foot,particularly while the threaded needle is withdrawing from the work.

The second presser foot lock comprises a vertical flange on the block 6%provided with teeth forming a ratchet 136 cooperating with a set of fourpawls 138 mounted for swinging movement on a pin 14d supported at itsends in a bracket 142. secured by screws 144 to the head frame (seeFIGS. 3 and 4). The pawls are pressed yieldingly against the ratchet1'36 by individual springs 14'6 mounted in openings in the bracket 142and engaging alined openings in the pawls. To disengage the pawls fromthe ratchet, a pair of links 148 are mounted for swinging movement onthe pin 140, one link being mounted at either side of the set of pawlsbetween the pawls and flange portions of the bracket 142. The links 148have passing through them a stud 154i being held from displacement fromthe links by cotters, one of which is shown at 152. The pin 14% also isheld in place by similar cotters 154. The stud 15% has projectingrearwardly of the rearmost link 148 a portion carrying a roll 156pressed yieldingly against a cam surface on a lever 15%. To press theroll against the cam surface of lever 158, one of the links 148 isengaged by a spring 160 compressed between the link and the bracket 142.The lever 158 is operated in proper timedrelation from the sewing shaftto cause the stud to disengage the pawls from the ratchet 136 before thepresser foot is lifted from the work in each sewing cycle. The lever 158which operates the presser foot ratchet lock is a part of a mechanismwhich imparts the feeding movement to the needle 2. by shifting theneedle and awl carrier 2%) in the direction of work feed while theneedle is .in engagement with the work, returning the carrier when theneedle is disengaged from the work.

To lift the presser foot from engagement with the work at the end of aseam, the rearward end of the rockshaft 54- has secured to it a bellcrank 178 (FIG. 3'), one arm of which is pivotally connected to adownwardly extending link 1% actuated in a manner to be described. Atthe end of a sewing operation the link 1% is moved downwardly, rockingthe shaft 554 in the proper direction to lift the presser foot to anelevated position where it .is held by the driving and stoppingmechanism until the machine is restarted. The timing of the lockingpawls 133 is such that they are disengaged from their ratchet 136 and sopermit the presser foot to be lifted in the stopped position of themachine.

With certain types of work, particularly when his necessary to cut astitch receiving groove in the work by means of a knife attached to thepresser foot, it is the practice to relieve the clamping pressure on thepresser foot without lifting it from engagement with the work as thework is fed. To enable the presser foot to remain in engagement with ashoe on the horn even though the presser foot bar 12 is lifted duringsewing operations, there is provided a yielding connection between thepresser foot and its bar. The yielding connection includes a sleeve 15?.(see FIG. 4) surrounding a reduced lower end of the presser foot bar.The bar is provided with a shoulder within the sleeve, between'whichshoulder and the lower end of the sleeve a. coil spring 184iscompressed. When the presser foot bar is lowered 'by its actuatingmechanism to clamp a shoe on the horn, the spring 184 yields until theupper end of the sleeve engages the block 69. When the bar 12 is liftedthe presser foot remains in engagement with the shoe throughout thelength of relative movement between the sleeve and the bar. To preventescape of the sleeve from the bar the lower end of the bar is threadedand carries a pair of check nuts 186 which may be adjusted to cause thepresser foot .to lift from engagement with the workin the regular 7manner or, alternatively, to remain yieldingly in engagement therewith.

To bring the presser foot yieldingly into engagement with the workbefore the application of a work clamping pressure and before theadjustment of a thread measuring mechanism which regulates the threadcontroller, the upper end of the presser foot bar 12 is surrounded by athreaded tube 188, best shown in FIG. 3. The threaded portion of thetube engages a threaded bearing in a bracket 1% (see also FIG. 2)secured to the upper portion of the head frame 40. Within the tube ismounted a coil spring 192 acting at its lower end against the upper endof the presser foot bar 12 and at its upper end on a button 194 pinnedto the upper end of the tube 188 and provided with a knurled edge tofacilitate manual rotation of the tube. By rotating the tube,compression of the spring 192 may be increased or decreased inaccordance with the nature of the work operated upon.

The work calipering feeler 38 is mounted for movement relative to thepresser foot 10. To enable the feeler to register the thickness of thework at the point where a stitch is being formed, it is located toengage the work to the rear of the line of the seam being inserted andalong the line of the seam in advance of the point of needle operation.The upper end of the feeler is clamped within a lug on a slide 196(FIGS. 3 and 4) guided on the presser foot bar for vertical movementrelative to the presser foot. The slide 196 has two bearing portionssurrounding the presser foot bar, one above the other. The lowermostbearing portion of the slide is formed with three arms, one of whichsupports the feeler 38, another of which forms a strut connected withthe uppermost bearing portion, and a third of which provides a guidebearing. At opposite sides of the presser foot bar the first and thirdmentioned arms projecting from the lower bearing portion are perforatedand receive in sliding engagement therewith a pair of vertical pins 198secured by set screws 200 in the head frame at The pins 198 preventrotation of the feeler slide while enabling the feeler to move freelyrelatively to the presser foot. The pins 198 also pass through closefitting openings in a crosshead at the lower end of the sleeve 1-82 toprevent angular displacement of the presser foot which is secured to thelower end of the sleeve. To secure the presser foot to the lower end ofthe sleeve 182, the presser foot has an upstanding slotted flangethrough the slot of which passes a clamp bolt 202, also entering anopening in the crosshead portion of the sleeve. The presser foot alsohas a clearance opening for the check nuts 186 and one of the pins 198.To limit the relative movement between the slide 196 and the presserfoot in a vertical direction, the sleeve 182 has clamped to it a collar284 between which and the crosshead the slide is confined. The positionof the collar is adjusted to enable the feeler 38 to project beyond thelower work-engaging surface of the presser foot or to be retracted fromthe level of the workengaging surface of the foot. The work measuringfeeler 38 is yieldingly urged toward the work by a light spring 210stretched between pins on the sleeve 182 and the slide 196. Connected tothe slide 196 are links for regulating the thread control function ofthe machine through mechanisms including a mechanical relay indicated at212 in FIG. 1. The thread control devices of the machine are more fullydescribed in the above-identified application, to which reference may behad for a fuller understanding.

The main sewing shaft 14 is driven and its speed controlled by a drivingand stopping mechanism 214 mounted in a hollow subframe 216 upon whichthe head frame is supported. The driving and stopping mechanism 214 iscontrolled by a treadle 218 extending forwardly from a base 220 uponwhich the subframe 216 is supported. The driving and stopping mechanismhas a drive shaft 222 connected to the main sewing shaft 14 by gearingincluding a pair of bevel gears 224, 226 mounted on the main sewingshaft and an inclined shaft 228 respectively (FIG.

2). At its lower end the shaft 228 is provided with a bevel gear 230meshing with a bevel gear 232 on the drive shaft 222. In addition to itsspeed regulating and stopping functions, the driving and stoppingmechanism 214 includes an arm 234 which is actuated as the machine isbeing brought to a stop for causing the vertical link to movedownwardly, as seen in FIGS. 1 and 3. The driving and stopping mechanismwill not be described further but may be more fully understood byreference to the parent application.

During the final rotational movements of the main sewing shaft 14 (seeFIG. 3) as the machine is coming to rest, a one-shot lubricating systemis actuated to apply oil to many of the operating parts. The lubricatingsystem is caused to be actuated by a connection with the presser footlifting rockshaft 54 which carries at its rearward end the bell crank178. For this purpose the upper arm of the bell crank 178 is pivotallyconnected to a rod 240 having a threaded end passing through aperforated block 242. The block 242 has a pair of trunnions enteringopenings in a forked arm of a lever 244 mounted for rotation on a stud246 fixed in a bracket 248 secured to the head frame 40. Another arm ofthe lever 244 is also forked and has open-ended slots entering itsforked portions, within the slots of which are positioned a pair ofalined pins, one of which is shown at 250 projecting from the upper endof a vertical plunger 252. The plunger 252 is slidable in a cylinder 254of an oil pump and at its upper end the plunger has a pair of spacedflanges between which is rotatably mounted a roll 256 engaging a camdisk 258 secured to the rearward end of the sewing shaft 14.

As the stopping mechanism is being actuated and the presser foot isbeing lifted at the end of a scam, the bell crank 178 is rotated in aclockwise direction, as viewed in \FIG. 3, pulling the rod 240 throughthe block 242 and pressing the roll yieldingly against the cam disk 258.For these purposes the rod is surrounded by a coil spring 260 compressedbetween the block 242 and a pair f check nuts 262 on the threadedportion of the rod. Just before reaching its final stopping position thespring 260 raises the plunger and a projection 264 on the cam disk 258engages the roll 256 to depress it sufiiciently to eject a quantity ofoil.

The lubrication cylinder 254 has an intake in a sump in the head frame40 beneath the sewing shaft 14 and discharges through branch lines, suchas that illustrated at 266 in FIG. 3, terminating in nozzles forlubricating the moving parts of the machine. The branch connection 266is shown with its nozzle disposed above the cam 42 for lubricating therolls 44 and 46 engaging the cam. When the machine is stopped, theplunger 252 is given a single reciprocation ejecting a shot of oil. Uponrestarting the machine, the roll 256 is given a second oil ejectingreciprocation. As the presser foot is being lowered into engagement witha new shoe, the rod 240 moves toward the left ('FIG. 3), releasing thecompression of the spring 266 and permitting the plunger 252 to bedepressed without causing it to be raised again. Depressing the plunger252 ejects the second shot of oil onto the moving parts of the machineand the plunger thereafter remains stationary in depressed positionuntil the machine stops.

Having described in detail an illustrative embodiment of the presentinvention in the form of a heavily constructed shoe sewing machine ofthe McKay type including a presser foot actuating mechanism, themovement of which may readily be adjusted from the exterior of themachine, mechanism for lifting the presser foot out of engagement withthe work piece at the end of the seam earlier or later according to thethickness of the work, and a positive lock of novel construction for thepresser foot, what we claim as new and desire to secure by LettersPatent of the United States is:

1. A McKay type shoe sewing machine having. a

frame, a sewing shaft in the frame, "stitch forming devices including aneedle actuated by the sewing shaft, a shoe supporting horn rotatable onthe frame, a presser foot for clamping the work on the horn, mechanismfor actuating the presser foot toward and from the horn comprising areciprocating bar to which the presser foot is attached, a rockshaftextending at right angles to the bar, operating connections between therockshaft and the presser foot bar, a presser foot lock, a floatinglever connected at one point along its length to the presser foot lock,an operating lever having an arm connected at another point on thefloating lever and a link connected between the rockshaft and a point onthe floating lever between the points of its connection with the lockand operating lever, and means for varying the effective length of thearm on the operating lever, in combination with an adjusting meansincluding a segment on. the frame for actuating the length varying meansto increase or decrease the movement imparted to the presser foot.

2. A McKay type shoe sewing machine having a frame, a sewing shaft inthe frame, stitch forming devices in- 'cluding a needle actuated by thesewing shaft, a shoe supporting horn rotatable on the frame, a presserfoot for clamping the work on the horn, mechanism for actuating thepresser foot toward and from the horn comprising a reciprocating bar towhich the presser foot is attached, a rockshaft extending at rightangles to the bar, operating connections between the rockshaft and thepresser foot bar, a presser foot lock, a floating lever connected at onepoint along its length to the presser foot lock, an operating leverhaving an arm connected at another point on the floating lever and alink connected between the rockshaft and a point on the floating leverbetween the points of its connection with the lock and operating lever,means for varying the effective length of the arm on the operating leverto enable the presser foot to be lifted from the work differentdistances with different thicknesses of work during sewing operations,driving and stopping mechanisms acting when the machine is brought torest to actuate the rockshaft in a direction to lift the presser footfrom the work, and means on the rockshaft for unlocking the presser footlock before the presser foot is raised, in combination with means forchanging the position of the unlocking means on the rockshaft to enablethe presser foot to be lifted earlier with thin work and later withthick work as the rockshaft is rocked.

3. A McKay type shoe sewing machine having a main frame, a sewing shaftin the frame, stitch forming devices including a hook needle actuated bythe sewing shaft, a work support, a presser foot for clamping the workon the work support, a mechanism for actuating the presser footcomprising an operating lever actuated by the sewing shaft, a floatinglever connected at one point along its length to the operating lever, apresser foot lock connected at another point on the floating lever, alink connected between the presser foot and a third point on thefloating lever, and means including an arm actuated by the sewing shaftfor locking and unlocking the presser foot lock, in combination with asecond locking means connected to the presser foot comprising a pawl andcooperating ratchet and means including a connection thereto operatedfrom the sewing shaft to disengage the pawl from the ratchet.

4. A McKay type shoe sewing machine having an enclosing frame, stitchforming devices in the frame including a hook needle, a rotatable shoesupporting horn, a presser foot, mechanism for actuating the presserfoot toward and from the horn to clamp or release a shoe thereoncomprising a reciprocating bar to which the presser foot is attached, afloating lever operatively connected to the bar at one point on thefloating lever, a cam actuated lever, a slot and block joint operativelyconnecting the cam actuated lever to the floating lever at a secondpoint thereon, a lock operatively connected to the floating lever at athird point thereon, and a for shifting the block along the slot of thejoint to vary the motion imparted to the presser foot by the presserfoot actuating mechanism, in combination with an adjusting memberconnected to the shifting link and projecting through the machine framefor actuating the link to shift relatively the slot and block of thejoint.

5. A McKay type shoe sewing machine having a frame, stitch formingdevices in the frame including a hook needle, a rotatable shoesupporting horn, a presser foot, a reciprocating bar and mechanism forreciprocating the bar, in combination with means including a sleevealin'ed with the reciprocating bar and slidably mounted in the: framefor reciprocation with the bar, to which sleeve the presser foot isattached, and a yielding connecting means acting between the bar and thesleeve to enable the presserfoot to remain in engagement with a shoe onthe horn as the presser foot bar is raised during sewing operations 6. AMcKay type shoe sewing machine having a-trarne, stitch forming devicesin the frame including a hook needle, a rotatable shoe supporting horn,a presser foot, a reciprocating bar and mechanism for reciprocatingthebar, in combination with means including a sleeve alined' with thereciprocating bar and slidably mounted in the frame for reciprocationwith the bar, to which sleeve the presser foot is attached, a yieldingconnecting means act-- ing between the bar and the sleeve to enable thepresser foot to remain in engagement with a shoe on the horn as thereciprocating bar is raised during sewing operations,

and a connection between the bar and the sleeve for limiting therelative movement therebetween.

7. A shoe sewing machine having an enclosing frame, stitch formingdevices in the frame including a hook.

needle, a work support, a presser foot, means for actuating the presserfoot toward and from the work support to clamp or release a shoe thereonincluding a floating lever operatively connected at one point to thepresser foot, a cam actuated lever, a slot and block joint oper--atively connecting the cam actuated lever to a second point on thefloating lever, a lock operatively connected to a third point on thefloating lever, in combination with means for shifting the block alongthe slot of the slot and block joint to vary the motion imparted to thepresser foot by the cam actuated lever including an adjusting memberconnected to the slot and sliding block joint and extending through theframe of the machine whereby the movement imparted to the presser footmay be quickly and conveniently adjusted by an operator.

8. A shoe sewing machine having a frame, a sewing shaft in the frame,stitch forming devices including a needle actuated by the sewing shaft,a work support, a presser foot adapted to clamp and release the work,means for actuating the presser foot toward and from the work supportincluding a rockshaft operatively connected-to the presser foot, apresser foot look, a floating lever connected at one point along itslength to the presser foot lock, an operating lever connected to anotherpoint on the floating lever, a link connected between the rockshaft anda point on the lever between the points of its connection with the lockand operating lever, driving and stopping mechanism including means foractuating the rockshaft as the mechanism is being brought to a stop tolift the presser foot from the work, and means on the rockshaft forunlocking the presser foot lock before the presser foot is raised incombination with means for changing the position of the unlocking meanson the rockshaft for causing the presser foot to be lifted earlier orlater in accordance with the thickness of the work being operated upon.

9. A McKay type shoe sewing machine having a main frame, a sewing shaftin the frame, stitch forming devices including a hook needle actuated bythe sewing shaft, a work support, a presser foot for clamping the workon the work support, a presser foot bar upon which the presser foot ismounted, a mechanism for actuating the presser foot comprising anoperating lever actuated bythe sewing shaft, :1 floating lever connectedat one point along its length to the operating lever, a presser footlock connected at another point onthe floating lever, a link connectedbetween the presser foot and a third point on the floating lever, andmeans including an arm actuated by the sewing shaft for locking andunlocking the presser foot lock, in combination with a second presserfoot locking means mounted directly on the presser foot bar.

10. A McKay type shoe sewing machine having a main frame, a sewing shaftin the frame, stitch forming devices including a hook needle actuated bythe sewing shaft, a work support, a presser foot for clamping the workon the work support, means effective during part of each sewing cyclefor locking the presser foot in engagement with the work and duringanother part of each sewing cycle to permit the position of the presserfoot to be adjusted in accordance with the varying thickness of the workand work feeding means, in combination with a second lock connected tothe presser foot comprising a pawl and a cooperating racthet andunlocking means connected directly to the work feeding means forreleasing the pawl before the work is fed.

11. A McKay type shoe sewing machine having a main frame, a sewing shaftin the frame, stitch forming devices including a hook needle actuated bythe sewing shaft, a work support, a presser foot for clamping the workon the work support, a mechanism for actuating the presser footcomprising an operating lever actuated by the sewing shaft, a floatinglever connected at one point along its length to the operating lever, apresser foot lock connected at another point on the floating lever, alink connected between the presser foot and a third point on thefloating lever, and means for locking the presser foot lock immediatelyafter the presser foot has engaged the work after the work has been fed,in combination with a second lock connected to the presser footcomprising a pawl and cooperating racthet, and means for disengaging thepawl from the ratchet before the presser foot is raised for feeding thework.

References Cited in the file of this patent UNITED STATES PATENTS272,740 Mills Feb. 20, 1883 1,925,513 Ashworth Sept. 5, 1933 2,001,308Hoppe May 14, 1935 2,331,118 Gouldbourn Oct. 5, 1943 2,731,929 AyresJan. 24, 1956

